<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style>
		* {
			margin: 0;
			padding: 0;
		}
		
		a {
			text-decoration: none;
		}
		header {
			height: 100px;
			width: 100%;
			background-color: #ccc;
			position: relative;
		}

		div {
			height: 80px;
			width: 100px;
			line-height: 80px;
			color: #fff;
			background-color: #FF3040;
			text-align: center;
			position: absolute;
			top: 10px;
			right: 10%;
			border: 1px solid #000;
		}

		div:hover {
			background-color: yellow;
			color: #000;
		}
	</style>
</head>
<body>
	<header>
		<a href="#">
			<div>
				哈哈
			</div>
		</a>
	</header>
</body>
</html>